Miles at sea and no way to escape-

Rumors of missing Nazi treasure are rampant in Europe in the wake of World War II, and Denmark, home to twelve-year-old twins Peter and Elise Andersen, is no exception. Hoping to strike it rich, Peter, Elise, and their friend Henrik begin investigating the mysterious site of a recent sinking in Helsingor Harbor. But when the twins and Henrik discover they are not the only ones interested in the sunken ship, their sleuthing leads them into greater danger than they ever imagined!

A split-second decision lands the three on a renegade German submarine staffed by a crazy crew that refuses to admit defeat. Suddenly, Peter, Elise, and Henrik are the only witnesses to a plot to smuggle priceless treasures out from under the noses of the Allied victors!